... I fail to understand why anybody would even bother 'emulating' it with new hardware.

The simplest reason would be to avoid carrying more hardware. I love my SP but since it's a unitasker I usually leave it out of my bag. Other potential reasons include, but are not limited to, ROM hacks, developing a deeper understanding of the technology and simply overcoming the challenge of emulating something correctly.

Similarly, it makes zero sense to buy an ebook from B&N if it is available through this program. So it does mean I am effectively locked into Amazon.

You're "effectively locked in" because they offer a better deal? You have no choice but to go for the cheapest option? Sorry, but that's like me saying I'm locked in to buying my groceries at Wal-Mart because they sell them cheaper than the local supermarket. While it may be more expensive we can both shop elsewhere if our morals dictate that the cheaper option is not the better one. If you don't trust Amazon don't give them your money. Then you can chalk the difference in price up to the cost of maintaining your morals.

If I had someone to practice with, sign language would be an interesting one to learn over Skype, provided you had decent cinematography on each end.

If you're looking for someone to learn sign language from I'd recommend visiting Conversation Exchange, Verbling or Italki. Since it's a constructed language you can become reasonably proficient in a few weeks. I taught myself to finger spell over an afternoon and could carry on an intermediate level conversation after about two weeks.

My father in law is one of those "too proud" people with regards to his hearing and having him in the house is an exercise in frustration. He doesn't have the radio too loud, when in fact it is nearly impossible to set the volume higher, we're just too sensitive. He doesn't have a hard time hearing us when we're practically yelling in his face, we're just not speaking up. Etc. In his case, however, I think the hardest part of convincing him to communicate with speakers of other languages or learn one himself is his old world belief that non-English speakers are inferior in some way.